June 14, 2007 -- Patients who have undergone
gastric bypass surgery to lose
weight already know they have to watch how much they eat after the operation to
keep that weight off. Now, a new study suggests they better keep a close eye on
their alcohol intake, too.

After the surgery, patients get tipsier faster and take longer to sober up,
says study researcher John M. Morton, MD, MPH, the director of bariatric
surgery at Stanford University School of Medicine.

"One drink could be enough to place them at risk for a DUI," Morton
tells WebMD.

The new study supports what gastric bypass surgeons have long suspected,
says Morton, who is presenting the findings this week at the 24th annual
meeting of the American Society for Bariatric Surgery in San Diego.

What Triggered the Study?

"We anecdotally know that patients have an altered sense of alcohol
[after the surgery]," Morton says. "It affects them quickly. My
patients often say, 'I get tipsy more easily' or 'I'm a cheap date
now.'"

In late 2006, the Oprah Winfrey show aired a segment titled "Suddenly
Skinny," which discussed the reactions gastric bypass patients can have to
alcohol, including some who began to binge drink, in effect trading a food
addiction for an alcohol addiction. Morton says he got numerous calls from his
concerned patients.

So Morton's team of researchers decided to see if science supports the
anecdotal observations that gastric bypass patients can't hold their liquor as
well as before.

The Study

The researchers compared the effects of drinking a 5-ounce glass of red wine
on 19 gastric bypass patients (whose weight had stabilized after the surgery)
and 17 people who had not had the surgery. The surgery patients' average age
was 47; the average age of the nonsurgery group was 37. The average weight of
the surgery group was 200 pounds; the average weight of the nonsurgery group
was 149. The bypass patients had gone, on average, from a
body mass index or
BMI of 51 to 33 (still considered obese).

Everyone was instructed to drink the wine within 15 minutes, and then
Morton's team measured the participants' breath alcohol levels every five
minutes until the levels returned to zero. The researchers measured how long it
took each person after finishing the drink to reach peak breath alcohol levels,
which Morton says correlate with blood alcohol levels, and how long it took for
the breath alcohol levels to return to zero.

All participants also reported any symptoms they had, such as euphoria,
dizziness, or slurred speech.

The surgery patients had an average peak alcohol breath level of 0.08% --
enough to be declared drunk when driving a motor vehicle. The nonsurgery
participants had a level of 0.05%.

The bypass patients took 108 minutes, on average, to normalize back to a
zero breath level of alcohol; the breath levels of alcohol of the nonsurgery
group returned to zero after 72 minutes.

Based on the levels and the time it took for them to normalize, the surgery
patients should have had more or greater symptoms than the nonsurgery group.
But surprisingly, "the symptoms were exactly the same," says Morton.
The surgery patients' symptoms "should have been more pronounced because
their peaks were higher and they took longer to normalize."

Interpretations of the Study

Based on the study findings, gastric bypass patients "are not
metabolizing alcohol the same way and not feeling the same way [as the
nonsurgery participants]," Morton tells WebMD.

The finding, he says, may explain why some experts have observed, and feared
-- that those who undergo bypass surgery might experience "addiction
transfer," in which they trade the addiction of binge eating, an issue for
many gastric bypass surgery patients, for an
alcohol addiction.

"This might account for some people becoming addicted to alcohol [after
bypass surgery]," Morton tells WebMD. "They may have to drink more to
get the same effect."

Physiologically, he says, there are explanations, too. The levels of a key
enzyme for metabolizing alcohol, called alcohol dehydrogenase, decline because
of the much smaller stomach size after gastric bypass surgery. Gastric
bypass and other weight loss surgeries reduce the stomach's capacity to a few
ounces. "This is probably why the alcohol peaks higher and stays
higher," Morton says.

Why the patients aren't feeling more symptoms is not known, he adds.

"Alcohol is not calorie-free, of course," Morton reminds his
patients. "A glass of wine has 125 calories. The other thing that happens
when you drink alcohol is it relaxes you both outside and inside -- your
esophagus and stomach also relax, and that allows you to eat more."

"I tell my patients to be careful with alcohol, and if they drink to do
so at home or to have a designated driver," Morton says.

Second Opinion

"This study supports our observations," says Philip Schauer, MD,
president of the Society for Bariatric Surgery and director of the Bariatric
and Metabolic Institute at Cleveland Clinic. "Because we are reducing
stomach capacity, food and liquor move rapidly into the intestines for
absorption."

More than 177,000 people in the U.S. had gastric bypass or other forms of
bariatric or weight loss surgery in 2006, according to estimates from the
Society. In consultations with his patients about what to expect after surgery,
Schauer says, "I usually tell them, 'One beer will feel like two.'"

SOURCES: John M. Morton, MD, MPH, director of bariatric surgery, Stanford University School of Medicine. Philip Schauer, MD, president, American Society for Bariatric Surgery, director of the Bariatric and Metabolic Institute, Cleveland Clinic. 24th Annual Meeting of the American Society for Bariatric Surgery, San Diego, June 11-16, 2007.